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Dynamics and Thermodynamics of Quantum Brownian Motion

Jishad Kumar

Published Sep 1, 2011• 0 citations
OpenAlex

Abstract

This thesis is all about the study of dynamics and thermodynamics of quantum Brownian motion. We mainly discussed the equilibrium properties of the dissipative quantum systems through a master equation approach to quantum Brownian motion as well as through a thermodynamical approach.

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The quantum master equation obtained by generalizing the geometric formulation of nonequilibrium thermodynamics to dissipative quantum systems is seriously nonlinear. We argue that nonlinearity occurs naturally in the step from reversible to irreversible equations and we analyze the nature of the nonlinear contribution. The thermodynamic nonlinearity leads to proper equilibrium solutions and improves the dynamic behavior of dissipative quantum systems. We also discuss the Markovian character of the thermodynamic quantum master equation. The general ideas are illustrated for two-level systems.
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